title: Trabecular bone scales allometrically in mammals and birds.
abstract: Many bones are supported internally by a latticework of trabeculae. Scaling of whole bone length and diameter has been extensively investigated, but scaling of the trabecular network is not well characterized. We analysed trabecular geometry in the femora of 90 terrestrial mammalian and avian species with body masses ranging from 3 g to 3400 kg. We found that bone volume fraction does not scale substantially with animal size, while trabeculae in larger animals' femora are thicker, further apart and fewer per unit volume than in smaller animals. Finite element modelling indicates that trabecular scaling does not alter the bulk stiffness of trabecular bone, but does alter strain within trabeculae under equal applied loads. Allometry of bone's trabecular tissue may contribute to the skeleton's ability to withstand load, without incurring the physiological or mechanical costs of increasing bone mass.
authors.affiliation: Department of Bioengineering, Imperial College London, South Kensington, London SW7 2AZ, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Doube
authors.forename: Michal M
authors.initials: MM
authors.lastname: Klosowski
authors.forename: Alexis M
authors.initials: AM
authors.lastname: Wiktorowicz-Conroy
authors.forename: John R
authors.initials: JR
authors.lastname: Hutchinson
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Shefelbine
mesh_terms: D000489:Alligators and Crocodiles / Q000033:anatomy & histology / Q000502:physiology; D000818:Animals; D001696:Biomechanical Phenomena; D001717:Birds / Q000033:anatomy & histology* / Q000502:physiology; D001835:Body Weight; D005269:Femur / Q000033:anatomy & histology* / Q000502:physiology; D020342:Finite Element Analysis; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000662:veterinary; D008322:Mammals / Q000033:anatomy & histology* / Q000502:physiology; D013045:Species Specificity; D013314:Stress, Mechanical; D055114:X-Ray Microtomography / Q000662:veterinary